Reference may be made to the following U.S. patents of interest: U.S. Pat. Nos. 3,738,025; 3,798,799; 3,848,347; 3,882,561; 4,083,127, all assigned to the same assignee as herein; and 3,832,792.
In ankle-covering boots or sports footwear, such as custom fitted ski boots and ice skates, it is desired to have the boot and its components adapted to surround and be contoured to custom-fit the wearer's foot. In such cases, the boot is to provide a support function for the wearer's foot and ankle and enable firm contact to be maintained between the foot and the outer shell of the ski boot.
Reference may be made to the aforementioned U.S. Pat. Nos. 3,798,799 and 3,882,561 wherein the custom fitting operation is disclosed. The aforementioned U.S. Pat. No. 4,083,127 additionally discloses the use of pressure-compensating fitting material used as fitting pads in conjunction with ski boots to maintain a snug or firm fitting relationship with the skier's foot during use to provide protection or comfort by cushion against pressure, impact or shock. Additionally, in view of the required substantially non-compressable stiff plastic material forming the shell of such boots, means may be provided on the boot to achieve adjustment in the normal boot stiffness, such adjustment being shown for instance in U.S. Pat. Nos. 3,738,025, 3,848,347 and 3,832,792.
It has been found however that, in some instances, when substantial pressure is applied to a ski boot as, for example, where a skier impacts the ground level following a jump or the like, the normally stiff boot shell has a tendency to momentarily "bow" or "balloon" in the ankle area. When this occurs, some skiers find this to be an undesirable reduction of support about the foot and ankle area.
It is therefore desired to obviate the "bowing" of the boot shell.